Hillary Clinton is appearing this morning before the House Select Committee on Benghazi to deliver her long-awaited testimony on the Sept. 11, 2012 attack that killed four Americans. 

She's expected to face tough questions about the security at the compound where Amb. Christopher Stevens was killed and the post-attack narrative put forth by the Obama administration. 

Since her appearance before Congress in Jan. 2013, it has emerged that Clinton used a private email server during her time as secretary of state.

That has led to questions from Committee Chairman Trey Gowdy (R-SC) about whether Clinton has disclosed all information about the attack.

Below, watch some video highlights from the hearing.

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In his opening statement, Gowdy said previous investigations into the attack by Congress and by the State Department's Accountability Review Board (ARB) were insufficient. 

He said investigators previously did not have access to the emails of Clinton and Amb. Stevens.

Here's a portion of his remarks.

Rep. Elijah Cummings (Md.), the ranking Democrat on the committee, slammed Republicans for what he sees as a politically-motivated investigation.

Cummings claimed that Republicans have been putting forth baseless allegations and wild conspiracy theories about the Benghazi attack.

Watch part of his opening statement.

Former Secretary of State Hillary Clinton delivered her opening statement, defending her decision to send Stevens to Benghazi. 

She argued that the United States cannot retreat from the world and that Stevens, like many other diplomats, understood the need to be on the ground despite security risks. 

Rep. Susan Brooks (R-IN) noted the huge discrepancy in the emails turned over related to Libya from 2011, and the much smaller pile of documents turned over from 2012. 

Clinton responded that for the most part, she did not conduct official business on her email. 

"I didn't conduct our nation's business on email," she said. 

Watch the exchange below.

Rep. Mike Pompeo (R-KS) went after Clinton for not firing anyone in the wake of the Benghazi attack. He said people in Kansas ask him "constantly" why no one has been held accountable for the death of a U.S. ambassador. 

Clinton pointed to the ARB investigation, saying it did not find anyone having breached their duties. 

"I followed the law," she said, adding there was no "dereliction of duty" found that would legally warrant a firing.

Pompeo put up a picture of an Islamist leader whom he said met with State Department "folks" just two days before the attack. 

Pompeo said Amb. Stevens sent a cable shortly before the attack about that meeting. 

"Were you aware that our folks were either wittingly or unwittingly meeting with al Qaeda on the ground in Benghazi, Libya, just hours before the attack?" he asked.

Clinton said she was not aware of the meeting.

Pompeo called that "deeply disturbing." Clinton then disputed that anyone on her "team" would have been involved in the meeting.

Watch the exchange below.

There were some fireworks between Rep. Trey Gowdy (R-SC) and Rep. Elijah Cummings (D-MD) over the numerous emails from Clinton confidant Sidney Blumenthal.

Clinton has said emails from Blumenthal were unsolicited, but Gowdy attempted to challenge that using the emails.

Cummings challenged him to release publicly the transcript of Blumenthal's appearance before the committee in order to give context to the emails.

Rep. Jim Jordan (R-Ohio) highlighted an email from Hillary Clinton to her family on the night of the Benghazi attack.

In the email, Clinton wrote that an "al Qaeda-like group" had attacked and that "two officers" were dead.

It's the first time this email has been disclosed. 

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